Ink
The staple medium for paleontological illustration is black ink. Artists can choose between using technical pens, crowquill pens, ultrafine markers, and brushes to apply the ink to their illustration. Grounds include papers such as hot press (smooth finish) bristol board, and drafting films such as Denril. Black ink against a white ground has the advantage of being very high contrast, which gives art a clarity not achieved with other media. This high contrast medium reproduces well in publication, even if inexpensive papers are used for printing. It is the visual equivalent to text.

The main pen and ink technques are: 1) stipple (an example of the stipple technique can be seen on the previous page) and; 2) line (an example of the line technique can be seen below).

In a stipple drawing, each stipple should be completely round, and no two stipples should touch. Shading is achieved by increasing the number of stipples in a given area. If using technical pens, sizes 3x0 for stipples and 2x0 for the outline of the specimen, with the illustration planned for a 50% reduction work well. The closer the structure of a specimen is to a viewer, the darker the line delineating that structure should be. The size of the stipple in the shading remains constant.

Sydney Prentice used the pen and ink thick / thin line (eyelash technique) to prepare this illustration of a fossil whale for Smithsonian curator Remington Kellogg. Prentice used a crowquill dip pen with a flexible nib. The flexible nib allows the artist to vary the thickness of the line by the pressure applied to the pen by the artist.